Purpose: To develop a method to normalize optical coherence tomography (OCT) signal profiles from two spectral-domain (SD-) OCT devices so that the comparability between devices increases. Methods: Twenty-one eyes from 14 healthy and 7 glaucoma subjects were scanned with two SD-OCT devices on the same day with equivalent cube scan patterns centered on the fovea (Cirrus HD-OCT, Carl Zeiss Meditec, Dublin, CA; and RTVue, Optovue, Fremont, CA). Foveola positions were manually selected and used as the center for registration of the corresponding images. A-scan signals were sampled 1.8 mm from the foveola in the temporal, superior, nasal and inferior ...

Purpose: To develop and test a novel signal enhancement method for optical coherence tomography (OCT) images based on the high dynamic range (HDR) processing concept. Methods: Three virtual channels, which represent low, medium, and high signal components, were produced for each OCT signal dataset. The dynamic range of each signal component was normalized to the full gray scale range. Finally, the three components were recombined into one image using various weights. Fourteen eyes of 14 healthy volunteers were scanned multiple times using time-domain (TD-) OCT before and while preventing blinking in order to produce a wide variety of signal strength ...

Aim To evaluate the utility of gold nanorods (AuNRs) as a contrast agent for ocular optical coherence tomography (OCT). Methods Mice were intravitreally injected with sterile AuNRs coated with either poly(strenesulfate) (PSS-AuNRs) or anti-CD90.2 antibodies (Ab-AuNRs), and imaged using OCT. After 24 h, eyes were processed for transmission electron microscopy or rendered into single cell suspensions for flow cytometric analysis to determine absolute numbers of CD45 + leukocytes and subsets (T cells, myeloid cells, macrophages, neutrophils). Generalised estimation equations were used to compare cell counts between groups. Results PSS-AuNRs and Ab-AuNRs were visualised in the vitreous 30 min and ...

Aims To evaluate the glaucoma discriminating ability of macular retinal layers as measured by spectral domain optical coherence tomography (SD-OCT). Methods Healthy, glaucoma suspect and glaucomatous subjects had a comprehensive ocular examination, visual field testing and SD-OCT imaging (Cirrus HD-OCT; Carl Zeiss Meditec, Dublin, California, USA) in the macular and optic nerve head regions. OCT macular scans were segmented into macular nerve fibre layer (mNFL), ganglion cell layer with inner plexiform layer (GCIP), ganglion cell complex (GCC) (composed of mNFL and GCIP), outer retinal complex and total retina. Glaucoma discriminating ability was assessed using the area under the receiver operator ...

Several in vitro and in vivo studies have established accelerated thrombolysis using ultrasound (US) induced microbubble (MB) cavitation. However, the mechanisms underlying MB mediated sonothrombolysis are still not completely elucidated. We performed three-dimensional (3-D) volumetric optical coherence tomography (OCT) imaging before and after the application of contrast US to thrombus. The most dramatic reduction in clot volume was observed with US + MB + recombinant tissue plasminogen activator (rt-PA). Thrombus surface erosion in this group on the side of the thrombus exposed to MB and ultrasound was evident on the OCT images. This technique may assist in clarifying the mechanisms underlying sonothrombolysis ...

Optical coherence tomography (OCT) provides in vivo cross-sectional and coronal imaging of the ocular fundus and anterior segment. Since its introduction in 1991, OCT evolved not only in its technical basis, from time domain to spectral domain, but also in the field of application, from structure to function. Increased resolution and scanning speed allow OCT to deliver high-quality structural information in a few seconds from the start of the acquisition to the final volumetric scan displayed on a computer screen. OCT provides both qualitative information, such as structural changes during followup, and quantitative parameters, such as the full thickness of ...